Dear Palepu Purna Sudhakar Rao
Good day! Thank you for posting in Microsoft Community. Please don't worry, we can work together to narrow down this behavior and solve it together.
Based on your description, it seems that when users click on events it shows the message which as Events added successfully in the page on your end and you want to edit this message based on your requirement.
If my understanding is correct, per our test and search, I'm afraid to tell you that there no settings or options in SharePoint can be used to edit this message. Apologize for the inconvenience caused due to the design behavior. Given this situation, we kindly suggest you submit a feedback in SharePoint · Community (microsoft.com) to make our products and services better for you and others. It is the best platform for us to listen to your opinions and make our products better serve you and others. which is the official suggestion box for SharePoint. Besides, other users also can’t find this function exactly, so please vote on the same post that will increase the awareness coming from the related team. The user voting here can let us better understand what users want, so that we can better improve our products.
If this is not your scenario or any unclear, you can post back in your free time. We’re looking forward to your reply and will continue to help you all the time!
Your kind understanding is highly appreciated. Stay safe and healthy always!
Sincerely,
Stacey | Microsoft Community Moderator